The present invention relates to a mechanism for transferring books or the like between work stations, and particularly relates to a mechanism for transferring books or the like between work stations in a bindery.
Heretofore various conveyor mechanisms have been used for moving books or the like between the various work stations in a bindery. Typically books are moved by various handling mechanisms between a trimmer and stitching station and also between a stitching station and the binder itself in which the books have a cover applied thereto. Typically these mechanisms for moving the books include chain conveyors with pushers which project above a raceway to engage the book and push the book along the raceway. Many of these pushers have been constructed of plastic or the like material. When the book moved thereby encounters a jam or the like providing a resistance to movement, these pusher pins frequently will break thus causing a stoppage in the machinery and of course a malfunction of the equipment. This necessitates repair of the equipment and can also cause lost time in operation of the entire bindery.
The present invention is directed to the solution of this particular problem and involves the use of a particular type of pusher finger construction which extends above the raceway in order to engage the books on the raceway to push the books along the raceway.
In accordance with the present invention, a pusher finger construction is provided which bends backwardly relative to the direction of movement thereof upon encountering a predetermined resistance to movement of the book which is being pushed thereby. As a result, the pusher finger construction, being moved continuously by the chain conveyor, can move past the book which is jammed. The pusher finger construction comprises at least one resiliently deflectable blade secured at one end to the conveyor chain and projecting in cantilever fashion therefrom over the raceway when pushing a book therealong. For purposes of increasing the force which the pusher finger construction can apply to the book without deflecting rearwardly, a plurality of blades can be utilized as opposed to a single blade.
Each pusher finger construction is secured to the conveyor chain by a lug. The lug has a surface which is curved in a direction extending transverse to the direction of movement of the book and the cantilever blades are likewise correspondingly curved so that the blades engage the lug over a surface area. Further, due to the fact that the blades are curved in a direction extending transverse to the direction of movement of the book the blades are strengthened over and above that provided if the blade were flat.
Further, the lug is curved in a direction parallel to the direction of conveyor movement and as the blades bend rearwardly, they curve around this curve of the lug. Thus when the blades are in the deflected position in which they are bent rearwardly, the blades have a full surface area contact with the lug.